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Zenith 7H920 AM/FM set 7 tube
#49

ordered up caps and since Gary at play things sent them out so quick, i dove into the cap can today.

my prior mods made it easy as pie.
pics below of the mod.
i have a ground conductor making a ring around the interior of the can for all the cap negatives to tie to per the schematic.

each individual terminal post 4 total was given a solid #12 pigtail to land the caps pos side.  this #12 continues down the bottom to the original solder tab where the other bits tie to.

my zenith was playing yesterday evening then it started to crackle and pop until no station could be heard and all that you could hear was the crackle and pop.  going up or down with the volume did not change the audibility of the crackle or pop.  It really sounded like silver mica disease inside some of those small IF's with slug tuning.  i powered down and took it out to the shop, measuring the caps they all were reading high,, like my 47uf were reading like 160,,, my 100uf was reading around 180.

thinking this is the issue i ordered up caps first then today i opened up the can.  i undid the 100uf cap and measured it.. its reading around 95uf.  all the other 47uf caps are reading fine as well.  maybe i had a lead touching somewhere underneath ,,, who knows.
All i know is that i soldered everything back and the set is playing now.  i ran a heat gun on top of the set while playing to simulate something over heating to make it fail quicker but its not.
right now i have it pushed up into the case and letting it play and get warm in its case.

so here are the pics of my rendition of the filter caps and how i did it.


Attached Files Image(s)
                   


Messages In This Thread
Zenith 7H920 AM/FM set 7 tube - by jcassity - 11-30-2018, 03:04 PM
RE: Zenith 7H020 AM/FM set 7 tube - by jcassity - 11-30-2018, 03:11 PM
RE: Zenith 7H020 AM/FM set 7 tube - by jcassity - 11-30-2018, 03:12 PM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 11-30-2018, 07:41 PM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 11-30-2018, 07:51 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-01-2018, 01:01 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-01-2018, 08:55 PM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-01-2018, 09:22 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-02-2018, 10:32 AM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-02-2018, 11:58 AM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-02-2018, 12:31 PM
RE: Zenith 7H920 AM/FM set 7 tube - by KCMike - 12-02-2018, 01:17 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-02-2018, 01:45 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-02-2018, 02:46 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-02-2018, 04:45 PM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-02-2018, 08:24 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-02-2018, 09:00 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-02-2018, 09:02 PM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-02-2018, 10:10 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-03-2018, 11:33 AM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-03-2018, 08:26 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-03-2018, 10:10 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-04-2018, 09:08 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-04-2018, 09:33 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-04-2018, 10:18 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-05-2018, 10:27 AM
RE: Zenith 7H920 AM/FM set 7 tube - by EdHolland - 12-05-2018, 02:30 PM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-05-2018, 05:22 PM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-05-2018, 08:41 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-05-2018, 10:53 PM
RE: Zenith 7H920 AM/FM set 7 tube - by Arran - 12-07-2018, 03:08 AM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-07-2018, 09:29 AM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-07-2018, 02:04 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-07-2018, 10:06 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-08-2018, 09:27 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-09-2018, 11:59 AM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-09-2018, 12:02 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-14-2018, 10:27 AM
RE: Zenith 7H920 AM/FM set 7 tube - by EdHolland - 12-14-2018, 02:41 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-14-2018, 04:27 PM
RE: Zenith 7H920 AM/FM set 7 tube - by LarryFS - 12-14-2018, 05:51 PM
RE: Zenith 7H920 AM/FM set 7 tube - by TV MAN - 12-15-2018, 11:48 AM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-15-2018, 02:16 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-17-2018, 08:13 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-18-2018, 08:25 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-18-2018, 10:01 PM
RE: Zenith 7H920 AM/FM set 7 tube - by David - 12-18-2018, 10:41 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-19-2018, 10:15 AM
RE: Zenith 7H920 AM/FM set 7 tube - by Ed Locker - 12-19-2018, 10:54 AM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-19-2018, 12:10 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-19-2018, 12:11 PM
RE: Zenith 7H920 AM/FM set 7 tube - by Ed Locker - 12-19-2018, 03:19 PM
RE: Zenith 7H920 AM/FM set 7 tube - by jcassity - 12-19-2018, 08:13 PM



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